Added atoi, atol, atoll plus internal helpers.

[pdclib] / functions / _PDCLIB / atomax.c

diff --git a/functions/_PDCLIB/atomax.c b/functions/_PDCLIB/atomax.c
new file mode 100644 (file)
index 0000000..bde1faf
--- /dev/null
+++ b/functions/_PDCLIB/atomax.c
@@ -0,0 +1,44 @@
+/* $Id$ */
+
+/* Release $Name$ */
+
+/* _PDCLIB_atomax( const char * )
+
+   This file is part of the Public Domain C Library (PDCLib).
+   Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#include <_PDCLIB_int.h>
+#include <string.h>
+#include <ctype.h>
+
+_PDCLIB_intmax_t _PDCLIB_atomax( const char * s )
+{
+    _PDCLIB_intmax_t rc = 0;
+    char sign = '+';
+    const char * x;
+    /* TODO: In other than "C" locale, additional patterns may be defined     */
+    while ( isspace( *s ) ) ++s;
+    if ( *s == '+' ) ++s;
+    else if ( *s == '-' ) sign = *(s++);
+    while ( ( x = memchr( _PDCLIB_digits, *(s++), 10 ) ) != NULL )
+    {
+        rc = rc * 10 + ( x - _PDCLIB_digits );
+    }
+    return ( sign == '+' ) ? rc : -rc;
+}
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+
+int main()
+{
+    BEGIN_TESTS;
+    /* basic functionality */
+    TESTCASE( _PDCLIB_atomax( "123" ) == 123 );
+    /* testing skipping of leading whitespace and trailing garbage */
+    TESTCASE( _PDCLIB_atomax( " \n\v\t\f123xyz" ) == 123 );
+    return TEST_RESULTS;
+}
+
+#endif